<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
  <title>background on non-HTML body should not fill the viewport</title>
  <style>
   html { background-color:transparent; background-image:none; }
   body { background-color:red; }
   p { background-color:lime; margin:0; }
  </style>
 </head>
 <body xmlns="urn:foo:bogus">
  <p xmlns="http://www.w3.org/1999/xhtml">This line should be green and there should be no red.</p>
 </body>
</html>